Fuel potential of bio-oil from co-pyrolysis of fresh palm fruit bunches and waste cooking oil sludge: composition, fuel properties, and carbon distribution analysis

This study investigates the co-pyrolysis of fresh palm fruit bunches (FFB) and waste cooking oil sludge (WCOS) in a batch pyrolyzer at various ratios (FFB:WCOS, 100:0 to 25:75). Increasing the WCOS ratio reduced the bio-oil yield (from 36.8 % to 25.8 %) but improved the quality. GC–MS revealed more long-chain alkanes, alkenes, and nitriles (e.g., hexadecanenitrile). The lower heating value rose to 42.2 MJ/kg, and the viscosity (2.7 cSt) was comparable to diesel fuel standards. These results indicate that co-processing FFB and WCOS produces bio-oils with favorable fuel properties, offering a sustainable route for the utilization of agricultural biomass and industrial waste.